Tandy 1000 Programmer's Reference Manual page 96

Chawter 1
I
System Calls
Ge tVer sion
Get Version Number Section Call 30H
Returns the
MS-DOS
version number. AL:AH contains the
2 part version designation on return. For example, for MS-
DOS
2.0, AL would contain 2 and AH would contain 0.
Entry Conditions:
AH = 30H
Exit Conditions:
AL
=
major version number
AH
=
minor version number
BH
=
OEM (original equipment manufacturer) number
BL:CX
=
24-bit user number.
Error Returns: None.
Example:
G e t V e r s l o n e q u
30H
mow a h , G e t V e r s i o n
i n t 21
H
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